contrib/bc/include/library.h

   1 /*
   2  * *****************************************************************************
   3  *
   4  * SPDX-License-Identifier: BSD-2-Clause
   5  *
   6  * Copyright (c) 2018-2023 Gavin D. Howard and contributors.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are met:
  10  *
  11  * * Redistributions of source code must retain the above copyright notice, this
  12  *   list of conditions and the following disclaimer.
  13  *
  14  * * Redistributions in binary form must reproduce the above copyright notice,
  15  *   this list of conditions and the following disclaimer in the documentation
  16  *   and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
  22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  *
  30  * *****************************************************************************
  31  *
  32  * The private header for the bc library.
  33  *
  34  */
  35
  36 #ifndef LIBBC_PRIVATE_H
  37 #define LIBBC_PRIVATE_H
  38
  39 #ifndef _WIN32
  40
  41 #include <pthread.h>
  42
  43 #endif // _WIN32
  44
  45 #include <bcl.h>
  46
  47 #include <num.h>
  48 #include <vm.h>
  49
  50 #if BC_ENABLE_MEMCHECK
  51
  52 /**
  53  * A typedef for Valgrind builds. This is to add a generation index for error
  54  * checking.
  55  */
  56 typedef struct BclNum
  57 {
  58         /// The number.
  59         BcNum n;
  60
  61         /// The generation index.
  62         size_t gen_idx;
  63
  64 } BclNum;
  65
  66 /**
  67  * Clears the generation byte in a BclNumber and returns the value.
  68  * @param n  The BclNumber.
  69  * @return   The value of the index.
  70  */
  71 #define BCL_NO_GEN(n) \
  72         ((n).i & ~(((size_t) UCHAR_MAX) << ((sizeof(size_t) - 1) * CHAR_BIT)))
  73
  74 /**
  75  * Gets the generation index in a BclNumber.
  76  * @param n  The BclNumber.
  77  * @return   The generation index.
  78  */
  79 #define BCL_GET_GEN(n) ((n).i >> ((sizeof(size_t) - 1) * CHAR_BIT))
  80
  81 /**
  82  * Turns a BclNumber into a BcNum.
  83  * @param c  The context.
  84  * @param n  The BclNumber.
  85  */
  86 #define BCL_NUM(c, n) ((BclNum*) bc_vec_item(&(c)->nums, BCL_NO_GEN(n)))
  87
  88 /**
  89  * Clears the generation index top byte in the BclNumber.
  90  * @param n  The BclNumber.
  91  */
  92 #define BCL_CLEAR_GEN(n)                                                       \
  93         do                                                                         \
  94         {                                                                          \
  95                 (n).i &= ~(((size_t) UCHAR_MAX) << ((sizeof(size_t) - 1) * CHAR_BIT)); \
  96         }                                                                          \
  97         while (0)
  98
  99 #define BCL_CHECK_NUM_GEN(c, bn)         \
 100         do                                   \
 101         {                                    \
 102                 size_t gen_ = BCL_GET_GEN(bn);   \
 103                 BclNum* ptr_ = BCL_NUM(c, bn);   \
 104                 if (BCL_NUM_ARRAY(ptr_) == NULL) \
 105                 {                                \
 106                         bcl_nonexistentNum();        \
 107                 }                                \
 108                 if (gen_ != ptr_->gen_idx)       \
 109                 {                                \
 110                         bcl_invalidGeneration();     \
 111                 }                                \
 112         }                                    \
 113         while (0)
 114
 115 #define BCL_CHECK_NUM_VALID(c, bn)    \
 116         do                                \
 117         {                                 \
 118                 size_t idx_ = BCL_NO_GEN(bn); \
 119                 if ((c)->nums.len <= idx_)    \
 120                 {                             \
 121                         bcl_numIdxOutOfRange();   \
 122                 }                             \
 123                 BCL_CHECK_NUM_GEN(c, bn);     \
 124         }                                 \
 125         while (0)
 126
 127 /**
 128  * Returns the limb array of the number.
 129  * @param bn  The number.
 130  * @return    The limb array.
 131  */
 132 #define BCL_NUM_ARRAY(bn) ((bn)->n.num)
 133
 134 /**
 135  * Returns the limb array of the number for a non-pointer.
 136  * @param bn  The number.
 137  * @return    The limb array.
 138  */
 139 #define BCL_NUM_ARRAY_NP(bn) ((bn).n.num)
 140
 141 /**
 142  * Returns the BcNum pointer.
 143  * @param bn  The number.
 144  * @return    The BcNum pointer.
 145  */
 146 #define BCL_NUM_NUM(bn) (&(bn)->n)
 147
 148 /**
 149  * Returns the BcNum pointer for a non-pointer.
 150  * @param bn  The number.
 151  * @return    The BcNum pointer.
 152  */
 153 #define BCL_NUM_NUM_NP(bn) (&(bn).n)
 154
 155 // These functions only abort. They exist to give developers some idea of what
 156 // went wrong when bugs are found, if they look at the Valgrind stack trace.
 157
 158 BC_NORETURN void
 159 bcl_invalidGeneration(void);
 160
 161 BC_NORETURN void
 162 bcl_nonexistentNum(void);
 163
 164 BC_NORETURN void
 165 bcl_numIdxOutOfRange(void);
 166
 167 #else // BC_ENABLE_MEMCHECK
 168
 169 /**
 170  * A typedef for non-Valgrind builds.
 171  */
 172 typedef BcNum BclNum;
 173
 174 #define BCL_NO_GEN(n) ((n).i)
 175 #define BCL_NUM(c, n) ((BclNum*) bc_vec_item(&(c)->nums, (n).i))
 176 #define BCL_CLEAR_GEN(n) ((void) (n))
 177
 178 #define BCL_CHECK_NUM_GEN(c, bn)
 179 #define BCL_CHECK_NUM_VALID(c, n)
 180
 181 #define BCL_NUM_ARRAY(bn) ((bn)->num)
 182 #define BCL_NUM_ARRAY_NP(bn) ((bn).num)
 183
 184 #define BCL_NUM_NUM(bn) (bn)
 185 #define BCL_NUM_NUM_NP(bn) (&(bn))
 186
 187 #endif // BC_ENABLE_MEMCHECK
 188
 189 /**
 190  * A header that sets a jump.
 191  * @param vm  The thread data.
 192  * @param l   The label to jump to on error.
 193  */
 194 #define BC_FUNC_HEADER(vm, l)     \
 195         do                            \
 196         {                             \
 197                 BC_SETJMP(vm, l);         \
 198                 vm->err = BCL_ERROR_NONE; \
 199         }                             \
 200         while (0)
 201
 202 /**
 203  * A footer for functions that do not return an error code.
 204  */
 205 #define BC_FUNC_FOOTER_NO_ERR(vm) \
 206         do                            \
 207         {                             \
 208                 BC_UNSETJMP(vm);          \
 209         }                             \
 210         while (0)
 211
 212 /**
 213  * A footer for functions that *do* return an error code.
 214  * @param vm  The thread data.
 215  * @param e   The error variable to set.
 216  */
 217 #define BC_FUNC_FOOTER(vm, e)      \
 218         do                             \
 219         {                              \
 220                 e = vm->err;               \
 221                 BC_FUNC_FOOTER_NO_ERR(vm); \
 222         }                              \
 223         while (0)
 224
 225 /**
 226  * A footer that sets up n based the value of e and sets up the return value in
 227  * idx.
 228  * @param c    The context.
 229  * @param e    The error.
 230  * @param bn   The number.
 231  * @param idx  The idx to set as the return value.
 232  */
 233 #define BC_MAYBE_SETUP(c, e, bn, idx)                                          \
 234         do                                                                         \
 235         {                                                                          \
 236                 if (BC_ERR((e) != BCL_ERROR_NONE))                                     \
 237                 {                                                                      \
 238                         if (BCL_NUM_ARRAY_NP(bn) != NULL) bc_num_free(BCL_NUM_NUM_NP(bn)); \
 239                         idx.i = 0 - (size_t) (e);                                          \
 240                 }                                                                      \
 241                 else idx = bcl_num_insert(c, &(bn));                                   \
 242         }                                                                          \
 243         while (0)
 244
 245 /**
 246  * A header to check the context and return an error encoded in a number if it
 247  * is bad.
 248  * @param c  The context.
 249  */
 250 #define BC_CHECK_CTXT(vm, c)                                   \
 251         do                                                         \
 252         {                                                          \
 253                 c = bcl_contextHelper(vm);                             \
 254                 if (BC_ERR(c == NULL))                                 \
 255                 {                                                      \
 256                         BclNumber n_num_;                                  \
 257                         n_num_.i = 0 - (size_t) BCL_ERROR_INVALID_CONTEXT; \
 258                         return n_num_;                                     \
 259                 }                                                      \
 260         }                                                          \
 261         while (0)
 262
 263 /**
 264  * A header to check the context and return an error directly if it is bad.
 265  * @param c  The context.
 266  */
 267 #define BC_CHECK_CTXT_ERR(vm, c)              \
 268         do                                        \
 269         {                                         \
 270                 c = bcl_contextHelper(vm);            \
 271                 if (BC_ERR(c == NULL))                \
 272                 {                                     \
 273                         return BCL_ERROR_INVALID_CONTEXT; \
 274                 }                                     \
 275         }                                         \
 276         while (0)
 277
 278 /**
 279  * A header to check the context and abort if it is bad.
 280  * @param c  The context.
 281  */
 282 #define BC_CHECK_CTXT_ASSERT(vm, c) \
 283         do                              \
 284         {                               \
 285                 c = bcl_contextHelper(vm);  \
 286                 assert(c != NULL);          \
 287         }                               \
 288         while (0)
 289
 290 /**
 291  * A header to check the number in the context and return an error encoded as a
 292  * @param c  The context.
 293  * number if it is bad.
 294  * @param n  The BclNumber.
 295  */
 296 #define BC_CHECK_NUM(c, n)                                         \
 297         do                                                             \
 298         {                                                              \
 299                 size_t no_gen_ = BCL_NO_GEN(n);                            \
 300                 if (BC_ERR(no_gen_ >= (c)->nums.len))                      \
 301                 {                                                          \
 302                         if ((n).i > 0 - (size_t) BCL_ERROR_NELEMS) return (n); \
 303                         else                                                   \
 304                         {                                                      \
 305                                 BclNumber n_num_;                                  \
 306                                 n_num_.i = 0 - (size_t) BCL_ERROR_INVALID_NUM;     \
 307                                 return n_num_;                                     \
 308                         }                                                      \
 309                 }                                                          \
 310                 BCL_CHECK_NUM_GEN(c, n);                                   \
 311         }                                                              \
 312         while (0)
 313
 314 //clang-format off
 315
 316 /**
 317  * A header to check the number in the context and return an error directly if
 318  * it is bad.
 319  * @param c  The context.
 320  * @param n  The BclNumber.
 321  */
 322 #define BC_CHECK_NUM_ERR(c, n)                         \
 323         do                                                 \
 324         {                                                  \
 325                 size_t no_gen_ = BCL_NO_GEN(n);                \
 326                 if (BC_ERR(no_gen_ >= (c)->nums.len))          \
 327                 {                                              \
 328                         if ((n).i > 0 - (size_t) BCL_ERROR_NELEMS) \
 329                         {                                          \
 330                                 return (BclError) (0 - (n).i);         \
 331                         }                                          \
 332                         else return BCL_ERROR_INVALID_NUM;         \
 333                 }                                              \
 334                 BCL_CHECK_NUM_GEN(c, n);                       \
 335         }                                                  \
 336         while (0)
 337
 338 //clang-format on
 339
 340 /**
 341  * Grows the context's nums array if necessary.
 342  * @param c  The context.
 343  */
 344 #define BCL_GROW_NUMS(c)                  \
 345         do                                    \
 346         {                                     \
 347                 if ((c)->free_nums.len == 0)      \
 348                 {                                 \
 349                         bc_vec_grow(&((c)->nums), 1); \
 350                 }                                 \
 351         }                                     \
 352         while (0)
 353
 354 /**
 355  * Frees a BcNum for bcl. This is a destructor.
 356  * @param num  The BcNum to free, as a void pointer.
 357  */
 358 void
 359 bcl_num_destruct(void* num);
 360
 361 /// The actual context struct.
 362 typedef struct BclCtxt
 363 {
 364         /// The context's scale.
 365         size_t scale;
 366
 367         /// The context's ibase.
 368         size_t ibase;
 369
 370         /// The context's obase.
 371         size_t obase;
 372
 373         /// A vector of BcNum numbers.
 374         BcVec nums;
 375
 376         /// A vector of BclNumbers. These are the indices in nums that are currently
 377         /// not used (because they were freed).
 378         BcVec free_nums;
 379
 380 } BclCtxt;
 381
 382 /**
 383  * Returns the @a BcVm for the current thread.
 384  * @return  The vm for the current thread.
 385  */
 386 BcVm*
 387 bcl_getspecific(void);
 388
 389 #ifndef _WIN32
 390
 391 typedef pthread_key_t BclTls;
 392
 393 #else // _WIN32
 394
 395 typedef DWORD BclTls;
 396
 397 #endif // _WIN32
 398
 399 #endif // LIBBC_PRIVATE_H